Ground Rules and Effective Analysis Techniques for Conducting Tabletop Exercises

In a previous issue of AWARE we looked at the benefits of tabletop response exercises between pipeline operators and emergency response organizations. This article looks at general “ground rules” for such drills, as well as tips to ensure that all parties get the most benefit out of the experience.

Tabletop exercises are discussion based sessions that allow participants to walk through a scenario (simulated incident) and discuss rolls and responsibilities and how an incident would be handled in a real situation. Effective exercises should ideally be interactive and designed to solicit comments and feedback from all participants. Key considerations that might be included in an exercise include impact zones, possible staging areas, and effects of weather, traffic patterns, evacuation considerations and discussions of where to establish Command Posts and resources that should be available to an Incident Commander.

The following ground rules can be used for Tabletop Exercises:
• Specific to the scenario that triggers the exercise, all key elements of the functional organization should be involved.
• The discussion should be designed to reinforce responsibilities and procedures.
• The focus should be on discussing resources, needs and high-level actions; ideally this drill should focus more on strategy than tactics.
• Necessary notifications to parties outside of the organization should be discussed and noted.
• Upon review, members will discuss the positive and negative points of the exercise and provide specific recommendations to improve performance.
• A report consisting of a summary of the incident, problems encountered, actions required and recommended solutions shall be prepared and distributed within the functional team for review.

Exercises should identify any gaps in plans or protocols. Ideally, strengths and weaknesses of the simulated response should be discussed immediately following the exercise, followed by a written summary that highlights specific elements for improvement and an action plan assigning responsibilities for facilitating such improvements. A sample of some action plan items is displayed below;

Pipeline Tabletop Exercises Foster Relationships with Emergency Responders

Developing and maintaining relationships with emergency responders in the communities in which we operate is a critical piece of Denbury Resources’ Public Awareness program. In addition to meeting face-to-face with emergency response personnel annually, we also invite them to participate in our annual tabletop drills. Tabletop exercises give us the chance to interact with emergency responders allowing for the opportunity to discuss specifics of pipeline operations and our associated emergency response procedures.

In preparation for a tabletop drill, local Denbury management personnel plan the exercise with scenarios ranging from a severe weather event to a pipeline leak. Tabletop drills typically begin with a safety briefing and an orientation. Exercises with operations personnel and any emergency responders attending will typically last around 2 hours. After the tabletop is completed, there is a quick debrief to discuss what worked, what didn’t, and what can be improved. These takeaways are not only operational but are also strategic, giving operations and emergency response personnel alike the opportunity to focus on better preparation in the event of an actual accident or incident.

During these tabletop exercises, emergency responders that attend are provided with county maps and Denbury brochures. Denbury county maps include basic information on the size, diameter, and location of the pipeline in each county, while brochures focus on specific properties of the product transported, recognizing a leak, and emergency contact information.

For more information on conducting a tabletop drill with Denbury, or for scheduled upcoming exercises, please email aware@denbury.com .

Pipeline Highlight: Gulf Coast Region

Denbury’s primary objective is on enhanced oil recovery utilizing carbon dioxide (CO2 EOR), and with 437.7 million barrels of oil equivalents (MMBOE) of estimated proved oil and natural gas reserves spaced across two key geographic regions, the Rocky Mountains and the Gulf Coast, our operations are very unique.

Our Gulf Coast region’s primary CO2 source comes from Jackson Dome near Jackson, Mississippi. It is believed that Jackson Dome is the only pure source of naturally occurring CO2 (98% CO2) east of the Mississippi River. Denbury Resources purchased Jackson Dome and the 183-mile NEJD CO2 pipeline in 2001. NEJD CO2 pipeline runs from Jackson Dome to near Donaldsonville, Louisiana. Since the acquisition of NEJD CO2 and Jackson Dome, we have acquired or constructed nearly 750-miles of CO2 pipelines in the region: the Free State Pipeline, The Green Pipeline Texas and the Green Pipeline Louisiana, Delta Pipeline, and the West Gwinville Pipeline.

The Green Pipeline, the largest of our pipelines in the area, runs from Donaldsonville, Louisiana and westward towards Hastings Field near Houston, Texas. The Free State Pipeline primarily transports CO2 to our four existing tertiary fields in East Mississippi (Eucutta, Soso, Martinville, and Heidelberg).

Our tertiary operations in the area include Delhi Field east of Monroe, Louisiana, Hastings Field south of Houston, Texas, Heidelberg and Tinsley Fields in Mississippi, and Oyster Bayou Field east of Galveston Bay, Texas. These fields account for 36% of our total CO2 EOR production in 2013 and approximately 21% of our year-end proved tertiary reserves.

Pipeline Safety: Safety Valves on CO₂ Pipeline Systems

All of the Denbury carbon dioxide (CO₂) pipeline systems utilize valves to control flow and relieve pressure within the pipelines. Valves are one method by which Denbury and other Operators are able to safely maintain and control the transportation of CO₂ by pipeline.

An automated valve is one that can be opened or closed using an electronic or pneumatic signal that causes a valve actuator to physically change the position of the valve (Open/Close). Denbury uses automated valves to isolate segments of their pipeline for maintenance, to control conditions along their pipeline systems and to protect their pipelines from operating outside of their design parameters. Automated valves can be operated remotely or locally or they can be designed to control conditions without any human intervention (i.e. Control Valves). Remotely controlled valves are operated from a remote location such as a central control center or field location. Valves in highly sensitive areas or remote locations are more likely to be remotely operated. Automated valves can also be operated locally, directly by Pipeline Operators who have the ability to isolate segments of the pipeline for maintenance activities and in order to maintain safe and efficient operating conditions. A control valve is a special category of automated valves designed to keep pipeline conditions as close as possible to a desired set point without any human intervention. These valves utilize complex control systems to sense pressure or flow conditions and automatically make corrections to keep the desired set point within a safe range.

Pressure relief valves and thermal relief valves are another category of valve, designed to prevent the internal pressure of the pipeline from reaching an established upper limit during operations (set point). This is accomplished by setting parameters on the valve that will allow the pressurized fluid to flow out of the system at the desired set point.

In the unlikely event of a CO₂ pipeline leak, a significant change in pipeline pressure would trigger an alarm at Denbury’s Gas Control Center (24/7 Operation) at which time a Pipeline Controller will initiate a command to close the upstream and downstream valves in order to isolate the affected pipeline segment. The benefits of monitoring the pipeline system conditions from a centralized 24/7 control center is that leaks can be detected quickly, the size of a subsequent release can be minimized, safety is enhanced along the pipelines and the downstream pipeline system is protected in the event of an operational upset. Other operating practices such as use of the One-Call system (811 Call Before you Dig), aerial patrol of the pipeline and personnel surveillance of the pipeline are additional tools that Denbury uses to keep our pipelines safe and leak-free.

Greencore Pipeline - Mainline Valve

Training Opportunity: Emergency Response Scenario for a CO₂ Pipeline

An example of an emergency response scenario for a CO₂ pipeline: It’s 4:30 p.m. on a Friday afternoon. A road construction contractor is conducting grading and drainage improvements in advance of a roadway resurfacing project on Highway 44. The crew foreman is pushing the track hoe operator to finish digging before a pending thunderstorm brings significant rainfall to the area.

As the track hoe bucket reaches for one more load of soil, the CO₂ pipeline is damaged; subsequently a loud roaring noise is heard followed by the initial development of a white vapor cloud in the excavation.

Shortly thereafter, the traffic on Highway 44 has increased and in some areas has come to a standstill. On-lookers have gathered in proximity to the rupture site and are taking pictures to post on social media sites.

A reporter and camera crew from 26 Eyewitness News has arrived on site and is requesting information from emergency responders and pipeline personnel.

Scenario Discussion Questions
• What are the strategic and tactical response priorities?
• What might the Incident Command System structure look like for this incident?
• What are the physical properties and hazards associated with the product being released?
• How are the public sector responders coordinating with the pipeline operator to respond to the incident?
• How is the traffic congestion and request from the news media personnel addressed?

This scenario can be used for discussion during a roll call or crew safety meeting. Are you familiar with how to handle a response to a CO₂ pipeline incident? Pipeline operators are eager to meet with public sector responders and discuss their operations and how to work together in the unlikely event of a pipeline emergency.

Carbon Dioxide Safety Data Sheet Quick Reference

Pipeline Highlight: Greencore Pipeline

Denbury’s first CO₂ pipeline in the Rocky Mountain Region was the 232-mile Greencore Pipeline completed in 2012. This 20-inch CO₂ pipeline begins at the ConocoPhillips Lost Cabin Gas Plant in Fremont County, Wyoming, and terminates at Denbury’s Bell Creek Field in Powder River County, Montana. The purpose of the Greencore Pipeline is to transport CO₂ to petroleum reservoirs for enhanced oil recovery in Denbury’s Rocky Mountain region. 

Enhanced oil recovery efforts such as Denbury’s operations result in the development of significant and otherwise stranded reserves of American oil from depleted reservoirs. This incremental production is extending the economic life and increasing the overall value of mature oil fields while providing considerable economic and environmental benefits. For more information on the Greencore Pipeline Project, please click here

Greencore Pipeline - Right of Way